Clamp lock anchor

ABSTRACT

A clamp lock anchor for clamping a reinforcement member during manufacture of pre-stressed concrete component. The clamp lock anchor comprises a barrel having a barrel screw thread engagement feature and a wall which defines a tapered internal cavity. The clamp lock further comprises an end cap comprising: a head; a shoulder which extends away from the head; an end cap screw thread engagement feature for engagement with the barrel screw thread engagement feature. The clamp lock also comprises a clamp assembly comprising: at least two clamp wedges which, when assembled: form a frusto-conical shaped body with a load application end at its widest end; and each wedge defining part of a through passage which provides a clamp surface for receiving the reinforcement member.

The present disclosure relates to a clamp lock anchor.

In particular the disclosure is concerned with a clamp lock anchor forclamping, and thus restraining, a reinforcement member duringmanufacture of a pre-stressed concrete component.

BACKGROUND

It is known to manufacture concrete products, for example slabs, beams,columns, wall and floor panels and other components or elements withreinforcement members such as wires, cables or rods, which are generallyreferred to as “tendons”. The concrete component may be formed in anynumber of ways.

For example, a mould or framework may be provided which defines theshape of the component to be made. Reinforcement members may be arrangedin the mould, and then concrete added and laid around the reinforcementmembers. In some instances the reinforcement members are pre-tensionedprior to the concrete being laid around them. Hence as the concrete isformed into the shape of the component it surrounds the reinforcementtendon, sets, and thereby holds the tendon in place.

The reinforcement tendon may be made from a metal wire (i.e. a singlemember) or a metal strand (comprising several wires), and so it isimportant that at no point in the process is the tendon allowed to goslack. If it does then the concrete component will not be capable ofholding the required and expected load for its design. Worse still, asudden release of the tendon can result in the free end of the tendonmoving at great speed which can cause severe damage and injury.

Hence a reliable means for clamping, and thus restraining, the tendonduring the manufacturing process is highly desirable.

SUMMARY

According to the present disclosure there is provided apparatus as setforth in the appended claims. Other features of the invention will beapparent from the dependent claims, and the description which follows.

Accordingly there may be provided a clamp lock anchor for clamping areinforcement member during manufacture of pre-stressed concretecomponent; the clamp lock anchor comprising: a barrel having: a barrelscrew thread engagement feature; and a wall which defines a taperedinternal cavity which extends between: a first opening with a firstdiameter at one end of the barrel; and a second opening at an oppositeend of the cavity with a second diameter smaller than the firstdiameter; an end cap comprising: a head; a shoulder which extends awayfrom the head; and an end cap screw thread engagement feature forengagement with the barrel screw thread engagement feature; a clampassembly comprising: at least two clamp wedges which, when assembled:form a frusto-conical shaped body with a load application end at itswidest end; and each wedge defining part of a through passage whichprovides a clamp surface for receiving the reinforcement member; thebarrel, end cap and clamp assembly being configured to co-operate suchthat, in use: when a reinforcement member is entered in the clampassembly; and the clamp assembly is located in the barrel cavity; theend cap screw thread is rotatable along the barrel screw thread suchthat the end cap shoulder transmits force to the load application end ofthe clamp assembly and thereby urges the clamp assembly into engagementwith the barrel internal cavity walls, thereby urging the clamp wedgestowards one another and clamping the reinforcement member.

The taper angle of the barrel internal cavity and the taper angle of thefrusto-conical shaped body may be substantially the same as each other.

The at least two clamp wedges may be biased towards one another by aresilient member.

The resilient member may be located towards one end of the clamp wedges.

The resilient member may be a band or resilient material. The resilientmember may be located in a groove provided in the barrel.

The clamp assembly through passage may be provided with at least onetooth which extends radially inwardly so as to engage with areinforcement member located in the clamp assembly through passage.

The clamp lock anchor may comprise two barrels of substantially similardesign; two clamp assemblies of substantially similar design, andwherein the end cap comprises: two shoulders, one shoulder extendingaway from one side of the head, the other shoulder extending away froman opposite side of the head; and two end cap screw thread engagementfeatures; the barrels, end cap and clamp assemblies being configured toco-operate such that, in use: a first reinforcement member is entered inone of the clamp assemblies, and a second reinforcement member isentered in the other clamp assembly; one of the clamp assemblies islocated in one barrel cavity, and the other clamp assembly is located inthe other barrel cavity; one of the end cap screw threads is rotatablealong one of the barrel screw threads; and the other end cap screwthread is rotatable along the other barrel screw thread; such that eachof the end cap shoulders transmits force to the load application end ofthe respective clamp assembly; and each of the clamp assemblies is urgedinto engagement with its respective barrel internal cavity walls,thereby urging the clamp wedges of each clamp assembly towards oneanother and clamping its respective reinforcement member to thereby linkthe two reinforcement members.

There may also be provided a reinforcement member pre-loading apparatuscomprising a clamp lock anchor according to the present disclosure.

There may further be provided a pre-stressed concrete componentmanufacturing apparatus comprising a reinforcement member pre-loadingapparatus according to the present disclosure.

Hence there is provided a clamp lock anchor for restraining areinforcement member, and thus maintaining tension in a reinforcementmember, a reinforcement member pre-loading apparatus and a pre-stressedconcrete manufacturing apparatus comprising a clamp lock anchor of thepresent disclosure, which will reliably grip a reinforcement memberprior to, and during, the forming and curing of a concrete component.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of the present disclosure will now be described with referenceto the accompanying drawings, in which:

FIG. 1 shows an example of a concrete component manufacturing apparatusaccording to the present disclosure;

FIG. 2 shows a side view of an alternative concrete componentmanufacturing apparatus according to the present disclosure

FIG. 3 shows a side view of a reinforcement member pre-tensioningarrangement according to the present disclosure;

FIG. 4 shows a view of an alternative reinforcement memberpre-tensioning apparatus arrangement according to the presentdisclosure;

FIG. 5 shows a cross-sectional view of a concrete product comprising areinforcing member;

FIG. 6 shows cross-sectional and end views of a barrel of a clamp lockanchor of the present disclosure;

FIG. 7 shows a side view and end views of clamp wedges of a clampassembly according to the present disclosure;

FIG. 8 shows clamp wedges of the clamp assembly shown in FIG. 7displaced apart from one another;

FIG. 9 shows the clamp wedges as shown in FIG. 7 and FIG. 8 with areinforcement member held between the clamp wedges;

FIG. 10 shows a side view and end view of an end cap for the clamp lockanchor;

FIG. 11 shows an assembled clamp lock anchor comprising the barrel, endcap and clamp assembly shown in FIGS. 6 to 10;

FIG. 12 shows a part exploded view of alternative example of a clamplock anchor according to the present disclosure for clamping two ends ofa reinforcement member together;

FIG. 13 shows a view of the clamp lock anchor of FIG. 14 when assembled;

FIG. 14 shows the motion and forces acting on the clamp wedges of theclamp lock anchor of the present disclosure when moved in a directionindicated by the arrow B; and

FIG. 15 shows a further view of the clamp wedges where they have beenmoved closer together than in the layout shown in FIG. 14.

DETAILED DESCRIPTION

FIG. 1 shows a pre-stressed concrete component manufacturing apparatus10 according to the present disclosure. It comprises a framework (ormould) 12 which, in the example shown, defines a cuboid shape, althoughit may be provided in any required shape. The framework 12 comprisesfour walls 14 and a base 16 which will constrain the concrete added toit. Apertures 18 are provided in the end walls of the mould 12 throughwhich reinforcement members/tendons 100 are passed so that thereinforcement members/tendons 100 can span the volume defined by theframework 12.

There is also provided a reinforcement member pre-loading apparatus 102which comprises plates (or “posts”) 108, 110 spaced apart from oneanother and disposed at either end of the framework 12. The plates 108,110 are part of a rigid structure for holding tendons 100 during aconcrete product manufacturing process. The plates 108, 110 may beattached to a superstructure which allows for them to maintain theirrelative position and orientation as it is important the tendons 100 areheld in place and at the desired tension.

In the example shown in FIG. 1 there is provided one reinforcementmember pre-loading apparatus 102 per framework 12. FIG. 2 shows analternative example where several frameworks 12 are placed in seriesbetween the posts 108, 110, with the reinforcement member/tendon 100extending through the series of frameworks 12.

In both examples anchors 120 according to the present disclosure areprovided at either ends of the reinforcement member to hold it onto theplates 108, 110 and thus maintain the position and tension in thereinforcement members/tendons 100. Additionally an alternative design ofanchor 124 according to the present disclosure may be provided along thelength of the apparatus 102 where it may be required to join lengths ofreinforcement members/tendons 100 together, for example, joining twolengths of tendon to create a longer tendon.

Jacks (or “rams”), shown as arrows “20” in FIGS. 1, 2 and 3 to indicatethe direction in which they act, are provided against the plate 108. Theplate 108 is moveable in a direction away from the framework 12 suchthat when the jack 20 acts upon the plate 108, it moves away from theframework 12 and plate 110, and thus tensions the tendon 100, the plate110 being maintained in a fixed position,

FIG. 3 shows the reinforcement member pre-loading apparatus 102comprising a clamp lock anchor 120 according to the present disclosure.For clarity, this is shown without the framework 12. Although thereinforcement member pre-loading apparatus 102 is shown in the figuresas being used in conjunction with a particular type of concretecomponent (i.e. “product”, “element” or “structure”) manufacturingapparatus 10, the reinforcement member pre-loading apparatus 102 mayalso be used in conjunction with concrete product manufacturingapparatus having alternative configurations.

As shown in FIG. 3, the pre-loading apparatus 102 comprises a jack 20which acts against the plate 108, sometimes referred to as an “abutment”post. The reinforcement member/tendon 100 may comprise a single wire(i.e. a single member) or a strand (comprising several wires). The wireor strand may comprise metal or metal alloys. Each plate 108, 110 has anorifice 112, 114 respectively through which the reinforcementmember/tendon 100 extends. The reinforcement member/tendon 100 thusextends through the clamp lock anchor 120, through the aperture 112 ofthe first plate 108 and then along the length of the region in which theconcrete components will be formed, and passed through aperture 114 ofthe second plate 110, and held by another clamp lock anchor 120 providedagainst on the second plate 110. That is to say, clamp lock anchors 120are provided at either end of the apparatus to grasp the reinforcementmember/tendon 100 where it extends out of and beyond the first plate 108and second plate 110.

As shown in FIG. 2, a further clamp lock anchor 124 may be providedbetween the plates 108, 110 to join two pieces of tendon material 100 a,100 b together to form a reinforcement member/tendon 100 of sufficientlength to span the length of the pre-loading apparatus 102. The jack 20may be left in position to maintain the tension in the reinforcementmember/tendon 100 throughout the time it takes for the concrete to cure.

In an alternative example, shown in FIG. 4, a different form of clampingmechanism 122 might be provided on the first plate 108 (i.e. the “jack”end) to grasp the tendon 100. In such an example, a clamp lock anchor120 is provided at the “dead” end of the arrangement (i.e. proximate tothe second plate 110), holding the reinforcement members/tendon 100against the plate 110. Initially the clamp lock anchor 120 at the deadend is tightened down on the reinforcement member/tendon 100 to clampthe clamp lock anchor 120 and reinforcement member/tendon 100 together.With the parts shown in FIG. 4 in place, the jack 22 is moved away fromthe mount plate 108 in a direction shown by arrow C in FIG. 4 to pullthe reinforcement member/tendon 100 against the second plate 110, theclamp lock anchor 120 at the dead end stopping the reinforcementmember/tendon 100 moving relative to the second plate 110. This puts thereinforcement member/tendon 100 into tension up to a load as requiredand desired by the user. Thus in this arrangement a jack 22 with jaws106 grasps the end of the reinforcement member/tendon 100 directly andpulls it to the desired extent before the clamping mechanism 122 isactuated to hold the tendon. The jack may then be removed leaving theclamping mechanism 122 at the jack end (opposite to the “dead end”) toprevent the reinforcement member/tendon 100 from moving relative to thefirst plate 108, and thereby maintains tension in the reinforcementmember/tendon 100.

As shown in FIG. 3, a plate 108, 110 may comprise several apertures 112,114 and used in conjunction with several clamp lock anchors 120. Hencethe jack may be used to pre-load several reinforcement members/tendons100 at the same time.

Alternatively, and as shown in FIG. 4, the pre-stressed concretemanufacturing apparatus may comprise one set of plates 108, 110 perreinforcement member/tendon 100. Thus several sets of plates 108, 110will be required to provide a number of reinforcement members/tendons100 in the same concrete product.

As stated above, the reinforcement member/tendon 100 extends through thevolume to be filled by concrete (e.g. the component 130 shown in FIG.5). After the concrete has been laid and has cured sufficiently, thejacks 20, 22 (if still present) are disengaged and the clamp lockanchors 120, 124 are removed, and since the pre-tensioned reinforcementmember/tendon 100 is held by the concrete, there is thus provided apre-stressed component 130. The product 130 is then removed from theframework 12.

FIGS. 6 to 13 show the elements of the clamp lock anchor 120 accordingto the present disclosure. FIG. 6 shows a main body, or “barrel” 200 ofthe clamp lock anchor 120 of the present disclosure. A cross-sectionalview is shown flanked on either side by end views of the same component.The barrel 200 has a wall 202 which defines an internal cavity 204. Theinternal cavity 204 has a first opening 206 with a first diameter at oneend of the barrel 200. It also has a second opening 208 at an oppositeend of the internal cavity 204 with a second diameter, where the seconddiameter is smaller than the first diameter of the first opening 206.The wall 202 which defines the internal cavity 204 extends between theopenings 206, 208 to define a tapered, or frusto-conical shaped, portionof the internal cavity 204. It further comprises an internal screwthread engagement feature 210. In the example shown the internal screwthread engagement feature 210 is provided towards, or at, the firstopening 206.

FIGS. 7, 8 and 9 show a clamp assembly 300. The clamp assembly 300comprises at least two clamp wedges (or “grips”) 302, 304 which, whenassembled, form a frusto-conical shaped body 306.

The clamp assembly 300 may comprise two or more clamp wedges 302, 304.For example depending on the shape or surface profile of thereinforcement member/tendon 100 to be clamped, it may be beneficial tohave three clamp wedges 302, 304 which, when assembled, form the frustoconical shaped body 306.

The frusto-conical shaped body 306 is provided with a load applicationend 308 at its widest end. When assembled, the two or more clamp wedges302, 304 also define a through passage 310 which provides a clampsurface for receiving a reinforcement member/tendon 100 as shown in FIG.9. That is to say, each wedge 302, 304 defines part of a through passage310 which is configured to provide a clamp surface for receiving andgrasping a reinforcement member/tendon 100.

The clamp wedges 302, 304 are biased towards one another by a resilientmember 312. The resilient member 312 may be provided at one end of theclamp wedges 302, 304. That is to say, the clamp wedges 302, 304 may bebiased towards one another by a resilient member 312 at one end of theclamp wedges 302, 304. Hence, the clamp wedges 302, 304 are pivotablerelative to one another, such that the clamp wedges 302, 304 can beangled relative to one another, coming together at the end where theyare biased together by the resilient member 312. The resilient member312 also allows for the clamp wedges 302, 304 to be spaced apart fromone another along their entire length. The resilient member 312 may belocated in a groove 314, and the groove 314 may be provided towards oneend of the clamp wedges 302, 304. The resilient member 312 may beprovided as a band of resilient material. For example, the resilientmember 312 might be a ring of rubber or the like, for example an O-ring.

The through passage 310 may be provided with at least one tooth 316, forexample provided as ribs or a screw thread on the inner surface of thepassage 310 which extend radially inwards. That is to say, the at leastone tooth 316 may extend radially inwardly towards the centre of thethrough passage 310 so as to engage with a reinforcement member/tendon100 located in the through passage 310.

The clamp lock anchor 120 further comprises an end cap 320 as shown inFIG. 10, which shows a side view and end views of the end cap 320. Theend cap 320 comprises a head (or “engagement feature”) 322, with, forexample, a diamond knurl or other surface configured for a user to holdand turn the end cap 320 (for example a polygonal nut shape, inparticular a hexagonal nut). In the example shown, the head 322 isformed at one end of the end cap 320. The end cap 320 further comprisesa shoulder 324 which extends longitudinally away from the head 322. Theend cap 320 further comprises an end cap screw thread engagement feature326 for engagement with the internal screw thread engagement feature210. In the example shown the end cap screw thread region 326 is locatedbetween the ends of the end cap 320. That is to say, the threaded region326 is provided between the engagement feature 322 and the shoulder 324in the longitudinal direction. The end cap 322 further comprises athrough passage 328 which opens at both ends of the end cap 322. In theexample shown, the through passage 328 extends from the engagementfeature end of the head 322 to the shoulder end 324 of the end cap 322.

The angle of the internal cavity 204 and the angle of the frusto-conicalshaped body formed by the clamp assembly 300 are substantially the sameas each other. That is to say, the profile of the outer surface of theclamp assembly 300 is complementary in shape to the internal profile ofthe barrel 200. Put another way, the taper angle of the internal cavity204 and the taper angle of the frusto-conical shaped body 300 aresubstantially the same as each other.

The geometries of the barrel 200, end cap 320 and clamp assembly 300 areconfigured such that the parts may co-operate to clamp a reinforcementmember/tendon 100. That is to say, and as shown in FIG. 11, when theclamp assembly 300 is located in the internal cavity 204, the end capscrew thread 326 is rotatable along the internal screw thread engagementfeature 210 such that the end cap shoulder 324 is in direct forcecommunication with the load application end 308 of the clamp assembly300 and thereby urges the clamp assembly 300 into engagement with thebarrel internal cavity walls 202. Put another way, the end cap 320 willtransmit force directly to the load application end 308 of the clampassembly 300. The end cap shoulder 324 may be in direct contact with theload application end 308 of the clamp assembly 300, that is to say,there may be nothing placed between the end cap shoulder 324 and theload application end 308. Alternatively an incompressible, orsubstantially incompressible, spacer (for example a washer) may beprovided between the end cap shoulder 324 and load application end 308of the clamp assembly 300, but because the spacer is incompressible, theshoulder 324 is in direct force communication with the clamp assembly300.

Since the end cap shoulder 324 is configured to be direct contact withthe clamp assembly 300, or at least in direct force communication withthe clamp assembly 300, every unit of length travelled by the end cap320 translates into a clamping force induced between the clamp surfacesof clamp wedges 302, 304.

FIGS. 12, 13 show the alternative example of the clamp lock anchor 124as previously described in relation to FIG. 2. The clamp lock anchor 124of FIGS. 12,13 comprises two barrels 200 and two clamp assemblies 300.That is to say, the clamp lock anchor 124 comprises a first barrel 200a, a second barrel 200 b, a first clamp assembly 300 a and a secondclamp assembly 300 b. The features of the barrels 200 a, 200 b, andclamp assemblies 300 a, 300 b are as previously described in relation tothe clamp lock anchor 120 shown FIGS. 6 to 9. Hence it comprises twobarrels 200 a, 200 b of substantially similar design and two clampassemblies 300 a, 300 b of substantially similar design. The clamp lockanchor 124 differs only in that its end cap 320′ is “double ended” inthat the threaded region 326 and end cap shoulder 324 extend from bothsides of a central head 322′ of the clamp lock anchor 124. That is tosay, the end cap (or “plug”) 320′ comprises two end cap shoulders 324, afirst end cap shoulder 324 a extending away from one side of the head322′, the second end cap shoulder 324 b extending away from an oppositeside of the head 322′. It also comprises two end cap threaded regions326 a, 326 b located to either side of the head 322′ of the end cap320′. Hence a first threaded region 326 a is provided between the firstend cap shoulder 324 a and the head 322′. The second threaded region 326b is provided between the second end cap shoulder 324 b and the head322′.

With reference to the example of FIG. 11, in operation the assembledclamp lock anchor 120 is threaded over the end of the reinforcementmember/tendon 100 such that the reinforcement member/tendon 100 passesthrough the through passage 328 of the end cap 320, passage 208 of thebarrel 200 and through passage 310 of the clamp assembly 300. The clamplock anchor 120 is located next to the plate 108/110 while the end cap320 is tightened up against the load application end 308 of the clampassembly 300 to urge the clamp assembly 300 along the length of thebarrel 200, for example in the direction shown by arrow B in FIG. 14.FIGS. 14, 15 show the clamp assembly 300 as it may appear in use insidethe barrel 200, but shown without the barrel 200, end cap 320 orreinforcement member/tendon 100 for clarity. Hence, the clamp wedges302, 304 may be spaced apart by a first distance as they clamp aroundthe reinforcement member/tendon 100, as shown in FIG. 14, held togetherby the resilient member 312.

As the end cap 320 is screwed into the barrel 200, the end cap shoulder324 of the end cap 320 is forced towards and transmits force to the loadapplication end 308 of the clamp wedges 302, 304 to push the clampassembly 300 in the direction shown by arrow B in FIG. 11 and FIG. 14.This causes the outer surface of the clamp assembly 300 to be pressedagainst the inner surface of the internal cavity 204 of the barrel 200,thus forcing the clamp wedges 302, 304 together as shown by arrow A inFIGS. 11, 14, reducing the distance between the clamp wedges 302, 304(for example as shown by the change in distance between the wedges 302,304 shown in FIG. 14 and FIG. 15). Hence the clamp wedges 302, 304 areclamped against the reinforcement member/tendon 100. As the internalcavity 204 and the frusto-conical shaped body 306 of the clamp assembly300 are complementary in shape, and the largest diameter of the clampassembly 300 is greater than the smallest diameter of the internalcavity 204 of the barrel 200, the clamp assembly 300 cannot pass out ofthe second opening 208 of the barrel 200.

Thus the wedges 302, 304 and clamp teeth 316 are urged towards oneanother to grip and clamp the reinforcement member/tendon 100.

The alternative (double ended) clamp lock anchor 124 shown in FIGS. 12,13 operates on the same principle. A first reinforcement member/tendon100 a is entered in the first clamp assembly 300 a, and a secondreinforcement member/tendon 100 b is entered in the second clampassembly 300 b. The first clamp assembly 300 a is located in the firstinternal cavity 204 a, and the second clamp assembly 300 b is located inthe second internal cavity 204 b.

The first threaded region 326 a is rotatable along the first internalscrew thread engagement feature 210 a and the second threaded region 326b is rotatable along the second internal screw thread engagement feature210 b such that each of the end cap shoulders 324 a, b directlytransmits force to the load application ends 308 a, 308 b of theirrespective clamp assemblies 300 a, b, as discussed above for the clamplock anchor 120. Consequently, each of the clamp assemblies 300 a, b isurged into engagement with its respective barrel internal cavity walls,thereby urging the clamp teeth of each clamp assembly 300 a, b towardsone another and clamping its respective reinforcement member/tendon 100a, 100 b to thereby link the two reinforcement members/tendons 100 a,100 b. That is to say, the clamp wedges 302, 304 at each end of theclamp lock anchor 124 are forced into engagement with the internal wallsof their respective barrel cavity, and thus are forced into engagementwith their respective reinforcement members/tendons 100 a, 100 b,thereby providing a means to robustly link reinforcement members/tendons100 a, 100 b together.

The direct contact and/or force transmission between the end cap andclamp assembly of both examples of clamp lock anchor 120, 124 allows foran initial clamp force to be set by a user which is predictable andpositive in that once a certain force has been applied to the end of theclamp assembly 300, the clamp wedge 302, 304 cannot open any further.Hence a user knows that having clamped the reinforcement member/tendon100, 100 a, 100 b by a device of the present disclosure, it cannotbecome released unless the end cap 320, 320′ is rotated relative tobarrel(s) to which it is engaged and hence slacken off the clamp wedges302, 304.

Having been initially clamped by a user, once tension is applied to thereinforcement member/tendon 100, 100 a, 100 b, the clamp wedges 302, 304are inherently drawn into their respective barrels 200, therebyincreasing the clamping force on the reinforcement member(s)/tendon(s)100, 100 a, 100 b.

Since the clamp lock anchors 120, 124 of the present disclosure areconfigured to grip a reinforcement members/tendons 100, 100 a, 100 b(for example a metal wire or metal strand comprising a plurality ofwires to form a tendon), they may be used in conjunction with anysuitable reinforcement member pre-loading apparatus, which may in turnbe used in conjunction with any suitable pre-stressed concretemanufacturing apparatus.

There is thus provided a clamp lock assembly 120, 124 which provides apositive lock on a reinforcement member/member 100, 100 a, 100 b. Thedirect contact and/or force transmission between the end cap shoulder324, 324 a, 324 b of the end cap 320, 320′ and the clamp wedges 302, 304means there is provided a constant clamping force on the reinforcementmember/tendon 100, 100 a, 100 b. The clamp wedges 302, 304 cannot becomeunclamped from the reinforcement member/tendon 100, 100 a, 100 b unlessthe end cap 320 is slackened off.

Hence, when the concrete has set around the reinforcement member/tendon100, a user may slacken the connection between the end cap 320, 320′ andassociated barrel 200, 200 a, 200 b, and thus withdraw clamp wedges 302,304 and barrel 200, 200 a, 200 b from the reinforcement member/tendon100, 100 a, 100 b. Thus the clamp lock anchors 120, 124 of the presentdisclosure may be re-used.

Additionally because of the simplicity of design of the clamp lockanchor 120, 124 of the present disclosure, when the clamp lock anchor120, 124 is cleaned, it is relatively easy to inspect and test. Only theresilient member 312 may need to be replaced on a regular basis.

Attention is directed to all papers and documents which are filedconcurrently with or previous to this specification in connection withthis application and which are open to public inspection with thisspecification, and the contents of all such papers and documents areincorporated herein by reference.

All of the features disclosed in this specification (including anyaccompanying claims, abstract and drawings), and/or all of the steps ofany method or process so disclosed, may be combined in any combination,except combinations where at least some of such features and/or stepsare mutually exclusive.

Each feature disclosed in this specification (including any accompanyingclaims, abstract and drawings) may be replaced by alternative featuresserving the same, equivalent or similar purpose, unless expressly statedotherwise. Thus, unless expressly stated otherwise, each featuredisclosed is one example only of a generic series of equivalent orsimilar features.

The invention is not restricted to the details of the foregoingembodiment(s). The invention extends to any novel one, or any novelcombination, of the features disclosed in this specification (includingany accompanying claims, abstract and drawings), or to any novel one, orany novel combination, of the steps of any method or process sodisclosed.

1. A clamp lock anchor for clamping a reinforcement member duringmanufacture of a pre-stressed concrete component, comprising: a barrelincluding a barrel screw thread engagement feature; and a wall that isconfigured to define a tapered internal cavity extending between a firstopening having a first diameter at a first end of the barrel; and asecond opening at a second end of the barrel, opposite the first end ofthe barrel, having a second diameter that is smaller than the firstdiameter; an end cap comprising: a head; a shoulder extendinglongitudinally away from the head; and an end cap screw threadengagement feature for engagement with the barrel screw threadengagement feature, the end cap screw thread engagement feature beingprovided longitudinally between the head and the shoulder; and a clampassembly comprising at least two clamp wedges which, when assembled,form a frusto-conical shaped body with a load application end at awidest end of the frusto-conical shaped body, each of the clamp wedgesdefining part of a through passage which provides a clamp surface forreceiving reinforcement member; the barrel, end cap and clamp assemblybeing configured to co-operate such that, when the reinforcement memberis positioned in the clamp assembly, and the clamp assembly is locatedin the barrel cavity, the end cap screw thread engagement feature isconfigured to be rotatable along the barrel screw thread engagementfeature such that the end cap shoulder is in direct force communicationwith the load application end of the clamp assembly to urge the clampassembly into engagement with the barrel wall, in turn, urging the clampwedges toward one another to clamp the reinforcement member.
 2. Theclamp lock anchor of claim 1, wherein the barrel, end cap and clampassembly are configured to co-operate such that, the end cap shoulder isin direct contact with the load application end of the clamp assembly.3. The clamp lock anchor of claim 1, wherein a taper angle of the barrelinternal cavity and a taper angle of the frusto-conical shaped body aresubstantially the same as each other.
 4. The clamp lock anchor of claim1, wherein the at least two clamp wedges are biased towards one anotherby a resilient member.
 5. The clamp lock anchor of claim 4 wherein theresilient member is located toward one end of the clamp wedges.
 6. Theclamp lock anchor of claim 5, wherein: the resilient member is a band orresilient material, and the resilient member is located in a grooveprovided in the barrel.
 7. The clamp lock anchor of claim 1, wherein theclamp assembly through passage is provided with at least one tooth thatextends radially inwardly and is configured to engage with thereinforcement member positioned in the clamp assembly through passage.8. The clamp lock anchor of claim 1, further comprising: two barrels ofsubstantially similar design; and two clamp assemblies of substantiallysimilar design, the end cap, comprising: two shoulders, a first shoulderextending away from a first side of the head in a longitudinaldirection, and a second shoulder extending away from a second andopposite side of the head in the longitudinal direction; and two end capscrew thread engagement features; the barrels, end cap and clampassemblies being configured to co-operate such that a firstreinforcement member is positioned in a first one of the two clampassemblies, and a second reinforcement member is positioned in a secondone of the two clamp assemblies; the first one of the two clampassemblies is positioned in a barrel cavity of the first one of the twobarrels, and the second one of the two clamp assemblies is positioned ina barrel cavity of the second one of the two clamp assemblies; a firstone of the end cap screw thread engagement features is rotatable alongthe barrel screw thread engagement feature of the first one of the twobarrels; and the second one of the end cap screw thread engagementfeatures is rotatable along the barrel screw thread engagement featureof the second one of the two barrels; such that each of the first andsecond end cap shoulders transmits force to the load application end ofeach respective clamp assembly; and each respective clamp assembly isurged into engagement with each respective barrel wall, thereby urgingthe clamp wedges of each respective clamp assembly toward one anotherand clamping a respective one of the first and second reinforcementmembers to thereby link the first and second reinforcement members.
 9. Areinforcement member pre-loading apparatus comprising: a clamp lockanchor for clamping a reinforcement member during manufacture of apre-stressed concrete component, comprising: a barrel including a barrelscrew thread engagement feature; and a wall that is configured to definea tapered internal cavity extending between a first opening having afirst diameter at a first end of the barrel; and a second opening at asecond end of the barrel, opposite the first end of the barrel, having asecond diameter that is smaller than the first diameter; an end capcomprising: a head; a shoulder extending longitudinally away from thehead; and an end cap screw thread engagement feature for engagement withthe barrel screw thread engagement feature, the end cap screw threadengagement feature being provided longitudinally between the head andthe shoulder; and a clamp assembly comprising at least two clamp wedgeswhich, when assembled, form a frusto-conical shaped body with a loadapplication end at a widest end of the frusto-conical shaped body, eachof the clamp wedges defining part of a through passage which provides aclamp surface for receiving the reinforcement member; the barrel, endcap and clamp assembly being configured to co-operate such that, whenthe reinforcement member is positioned in the clamp assembly, and theclamp assembly is located in the barrel cavity, the end cap screw threadengagement feature is configured to be rotatable along the barrel screwthread engagement feature such that the end cap shoulder is in directforce communication with the load application end of the clamp assemblyto urge the clamp assembly into engagement with the barrel wall, inturn, urging the clamp wedges toward one another to clamp thereinforcement member.
 10. The reinforcement member pre-loading apparatusof claim 9, wherein the barrel, end cap and clamp assembly areconfigured to co-operate such that, the end cap shoulder is in directcontact with the load application end of the clamp assembly.
 11. Thereinforcement member pre-loading apparatus of claim 9, wherein a taperangle of the barrel internal cavity and a taper angle of thefrusto-conical shaped body are substantially the same as each other. 12.The reinforcement member pre-loading apparatus of claim 9, wherein theat least two clamp wedges are biased toward one another by a resilientmember.
 13. The reinforcement member pre-loading apparatus of claim 12,wherein the resilient member is located toward one end of the clampwedges.
 14. The reinforcement member pre-loading apparatus of claim 13,wherein the resilient member is a band or resilient material, and theresilient member is located in a groove provided in the barrel.
 15. Thereinforcement member pre-loading apparatus of claim 9, wherein the clampassembly through passage is provided with at least one tooth that isconfigured to extend radially inwardly to engage with the reinforcementmember positioned in the clamp assembly through passage.
 16. Thereinforcement member pre-loading apparatus of claim 9, furthercomprising: two barrels of substantially similar design; and two clampassemblies of substantially similar design, the end cap comprising: twoshoulders, a first shoulder extending away from a first side of the headin a longitudinal direction, and a second shoulder extending away from asecond and opposite side of the head in the longitudinal direction; andtwo end cap screw thread engagement features; the barrels, end cap andclamp assemblies being configured to co-operate such that a firstreinforcement member is positioned in a first one of the two clampassemblies, and a second reinforcement member is positioned in a secondone of the two clamp assemblies; the first one of the two clampassemblies is positioned in a barrel cavity of the first one of the twobarrels, and the second one of the two clamp assemblies is positioned ina barrel cavity of the second one of the two clamp assemblies; a firstone of the end cap screw thread engagement features is configured to berotatable along the barrel screw thread engagement feature of the firstone of the two barrels; and the a second one of the end cap screw threadengagement features is configured to be rotatable along the barrel screwthread engagement feature of the second one of the two barrels; suchthat each end cap shoulder transmits force to the load application endof each respective clamp assembly; and each respective clamp assembly isurged into engagement with each respective barrel wall, thereby urgingthe clamp wedges of each respective clamp assembly toward one anotherand clamping a respective one of the first and second reinforcementmembers to thereby link the first and second reinforcement members. 17.A pre-stressed concrete component manufacturing apparatus comprising: areinforcement member pre-loading apparatus including a clamp lock anchorfor clamping a reinforcement member during manufacture of a pre-stressedconcrete component, comprising, the clamp lock anchor, comprising: twobarrels of substantially similar design, each of the two barrelsincluding (1) a barrel screw thread engagement feature, and (2) a wallthat is configured to define a tapered internal cavity extending betweena first opening having a first diameter at a first end of the barrel,and a second opening at a second end of the barrel, opposite the firstend of the barrel, having a second diameter that is smaller than thefirst diameter; and two clamp assemblies of substantially similar designeach of the two clamp assemblies including at least two clamp wedgesthat, when assembled, form a frusto-conical shaped body with a loadapplication end at a widest end of the frusto-conical shaped body, eachof the clamp wedges defining part of a through passage that provides aclamp surface for receiving the respective reinforcement member; and anend cap comprising: a head; two shoulders, a first shoulder extendingaway from a first side of the head in a longitudinal direction, and asecond shoulder extending away from a second and opposite side of thehead in the longitudinal direction, and first and second end cap screwthread engagement features, the first and second end cap screw threadengagement features being provided longitudinally between the head andthe respective first shoulder and second shoulder, the barrels, end capand clamp assemblies being configured to co-operate such that a firstreinforcement member is positioned in a first one of the two clampassemblies, and a second reinforcement member is positioned in a secondone of the two clamp assemblies; the first one of the two clampassemblies is positioned in a barrel cavity of the first one of the twobarrels, and the second one of the two clamp assemblies is positioned ina barrel cavity of the second one of the two clamp assemblies; a firstone of the end cap screw thread engagement features is configured to berotatable along the barrel screw thread engagement feature of the firstone of the two barrels; and the a second one of the end cap screw threadengagement features is configured to be rotatable along the barrel screwthread engagement feature of the second one of the two barrels; suchthat each end cap shoulder transmits force to the load application endof each respective clamp assembly; and each respective clamp assembly isurged into engagement with each respective barrel wall, thereby urgingthe clamp wedges of each respective clamp assembly toward one anotherand clamping a respective one of the first and second reinforcementmembers to thereby link the first and second reinforcement members.